add libc building to agbcc.

1 files changed, 49 insertions, 0 deletions

diff --git a/libc/math/sf_isnan.c b/libc/math/sf_isnan.c
new file mode 100644
index 0000000..8fdb6ad
--- /dev/null
+++ b/libc/math/sf_isnan.c
@@ -0,0 +1,49 @@
+/* sf_isnan.c -- float version of s_isnan.c.
+ * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
+ */
+
+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * Developed at SunPro, a Sun Microsystems, Inc. business.
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice 
+ * is preserved.
+ * ====================================================
+ */
+
+/*
+ * isnanf(x) returns 1 is x is nan, else 0;
+ * no branching!
+ */
+
+#include "fdlibm.h"
+
+#ifdef __STDC__
+	int isnanf(float x)
+#else
+	int isnanf(x)
+	float x;
+#endif
+{
+	__int32_t ix;
+	GET_FLOAT_WORD(ix,x);
+	ix &= 0x7fffffff;
+	ix = 0x7f800000 - ix;
+	return (int)(((__uint32_t)(ix))>>31);
+}
+
+#ifdef _DOUBLE_IS_32BITS
+
+#ifdef __STDC__
+	int isnan(double x)
+#else
+	int isnan(x)
+	double x;
+#endif
+{
+	return isnanf((float) x);
+}
+
+#endif /* defined(_DOUBLE_IS_32BITS) */